The invention relates to a fuel injector for a fuel injection system of an internal combustion engine with a high pressure pump for supplying fuel under pressure, by way of a fuel supply line, to at least one injector including an injection nozzle with a valve needle. The injector is electrically controllable and includes a pressure relieve passage leading to a low pressure fuel return line and a flow limiter for limiting the maximum fuel flow volume.
A fuel injection system with a high pressure fuel pump is disclosed for example in EP 0 678 602 A2. In this system, the high pressure pump supplies the fuel, by way of a fuel supply line, to a commom rail distribution pipe, which serves as a high pressure fuel storage structure for supplying fuel to all the magnetic valve-controlled injectors of the internal combustion engine.
The fuel injection system includes flow volume limiting valves arranged in injection lines extending between the injectors and the common rail pipe. The flow volume limiting valves are adapted to limit the fuel flow to the injectors so as to prevent excessive flow rates as they may occur for example when a valve needle gets stuck or a valve needle breaks or a high pressure line becomes defective.
With such measures, the properly operating valves and the non-defective fuel lines can still be operated so that at least an emergency operation of the engine can be maintained.
It is the object of the present invention to provide a fuel injection system of the type referred to above with a fuel flow limiting valve, wherein the fuel volume contained in the system between the valve needle seat and the flow volume limiting valve is minimized.